$(function()
{
	
	$('#submit').click(function(){
		var amount = $('#amount').val();
		$.ajax(
		{
			type: 'POST',
			url: '/billing/addnew',
			data: 'amount=' + encodeURIComponent( amount ) ,
			dataType: 'json',
			async: false, 
			success: function(r)
			{
			  $('#item_number').val(r.ret);
			}
		});	
		alert($('#item_number').val());
		
	});
	
});